Merriam-Webster Collegiate Dictionary - barb

 I. noun  Etymology: Middle English ~e ~, beard, from Anglo-French, from Latin ~a — more at beard  Date: 14th century  1. a medieval cloth headdress passing over or under the chin and covering the neck  2.  a. a sharp projection extending backward (as from the point of an arrow or fishhook) and preventing easy extraction; also a sharp projection with its point similarly oblique to something else  b. a biting or pointedly critical remark or comment  3. ~el II  4. any of the side branches of the shaft of a feather — see feather illustration  5. a plant hair or bristle ending in a hook  • ~less adjective  II. transitive verb  Date: 1759 to furnish with a ~  III. noun  Etymology: French ~e, from Italian ~ero, from ~ero of Barbary, from Barberia Barbary, coastal region in Africa  Date: 1636 any of a northern African breed of horses that are noted for speed and endurance  IV. noun  Date: 1967 slang ~iturate